1. Field of the Invention
The present invention relates to methods for improving water and soil and to ecologically beneficial bioremediation, manufacturing, and recycling methods. The invention further relates, more particularly, to ecologically beneficial methods for making pulp and paper products.
2. Description of Related Art
Bioremediation of wastewater from, for example, wetlands or municipal effluent has been successfully accomplished with the use of species of plants that remove excess nutrients. Wetland filtration is one such method of bioremediation, but it requires relatively large land areas to accomplish wastewater cleanup. In addition, the nutrients are generally left in situ and can under some circumstances be rereleased into the environment, such as in a dry-year fire or through succession.
Other methods use attached algal colonies known as periphyton, which utilize biological pathways to remove and degrade a wide spectrum of pollutants, such as excess phosphorus, nitrogen, carbon, alkaline earth metals, and heavy metals (Adey, U.S. Pat. No. 4,333,263; Jensen, U.S. Pat. Nos. 5,131,820, 5,527,456, 5,573,669, and 5,591,341, the disclosures of which are incorporated herein by reference). Periphyton filtration requires far less land area than wetland filtration and also retains the nutrients in a confined area from which the algae and ingested or sequestered nutrients may be harvested.
Periphyton filtration has been shown to remove a wide array of nutrients and other contaminants usually occurring at low levels when compared with municipal wastewater. The attached algae are known to grow at rates exceeding those of terrestrial plants, and a periphyton filtration system can generate large masses of algae that need to be disposed of after harvesting, typically by transportation from the bioremediation site to another area for introduction into the soil or to be used as livestock feed.
It is known to use the harvested algal biomass as a fertilizer (Snyder and Adey, unpublished, June, 1993) and in pulp production (Sakai et al., U.S. Pat. No. 5,500,086). It is also known to use pulp from recycled paper products to mold packaging and containers (Emery International Developments, Ltd., Toronto, Ontario, Canada, January, 1995).
It is therefore an object of the present invention to provide an integrated system and method for utilizing biomass harvested from a bioremediation process to produce recycled pulp and paper products.
It is another object to provide such a system and method to produce such a biodegradable product that can be further recycled for use as a soil additive.
It is a further object to provide such a system and method that links an enhanced biological filtration technique, manufacturing technology, and a packaging product to export nutrients from a bioremediation site.
A first embodiment of the method of the present invention is for producing pulp for use in making a packaging material. The method comprises the steps of culturing plant matter in a bed and running water to be treated thereover. The plant matter should have the attribute of being able to absorb or sequester the material desired to be removed from the water. In a specific embodiment the plant matter comprises algae in an attached periphyton bed. The plant matter in the bed is permitted to absorb pollutants/nutrients from the water, which serves to bioremediate the water.
After the algae has had sufficient time to absorb and/or sequester the material/pollutants that are desired to be removed, and the bed has grown to a predetermined level, the algae are harvested, which removes the pollutants from the periphyton bed. The harvested algae produce a wet algal biomass, which is then mixed with a shredded paper product to produce a pulp.
The pulp can be used, for example, to make packaging, which is biodegradable in soil and, when added in an approximate range of 10-25% by volume, has been shown to improve dramatically the quality of the soil. In addition, the packaging itself can serve as a vehicle for removing the excess nutrients from the bioremediation site or basin, thereby increasing the ecological efficacy and benefits of the method.
In a second embodiment, another bioremediation plant, a combination of more than one of such plants, or a combination of one or more of such plants with algae is used as the biomass.
In a third embodiment, the first embodiment of the method and system as described above is extended to make a paper product from the pulp produced thereby.
The features that characterize the invention, both as to organization and method of operation, together with further objects and advantages thereof, will be better understood from the following description used in conjunction with the accompanying drawing. It is to be expressly understood that the drawing is for the purpose of illustration and description and is not intended as a definition of the limits of the invention. These and other objects attained, and advantages offered, by the present invention will become more fully apparent as the description that now follows is read in conjunction with the accompanying drawing.